The invention provides a method for preparing a non-fried instant freshwater fish, comprising the concrete steps of preparing a raw material fish, carrying out pretreatment (scale, head, tail and innards removing), washing clearly, cutting and shaping, soaking in ice water, soaking in water containing salt and vinegar, curing at a low temperature, draining, performing roast smoking, stoving, baking, spouting oil, filling, carrying out vacuum seal and microwave sterilization, boxing up to obtain the finished product. The fish prepared by adopting the method for preparing the non-fried instant freshwater fish has the advantages of no fishy smell, good taste, no poisonous or harmful substance of fried foods, little oil content and capability of guaranteeing the product quality.